சோ - பெயர்க்காரணம்
7 years ago
Summary
Dr. Brizendine discusses her latest book, The Male Brain: A Breakthrough Understanding of How Men and Boys Think. An article about Dr. Louann Brizendine and her research in her first book The Female Brain in a July 2006 issue of Newsweek started a media frenzy that led to appearances on GMA's "20/20" and "Good Morning America," NBC's "The Today Show" and "News with Brian Williams," CNN's "American Morning," NPR's "Weekend All Things Considered," "Wait, Wait Don't Tell Me" along with national print reviews and features in USA Today, The New York Times, The New York Times Magazine, The Washington Post, The San Francisco Chronicle, O,The Oprah Magazine, Glamour, Elle, More, Discover, Health, and the coverage has not abated.
Now, Brizendine, founder of the country's first clinic to study gender differences in brain, behavior, and hormones, turns her attention to the male brain, showing how the "male reality" is fundamentally different from the female’s in every phase of life, from babyhood to old age. In The Male Brain: A Breakthrough Understanding of How Men and Boys Think, Brizendine overturns the stereotypes about men and boys. Impeccably researched and at the cutting edge of scientific knowledge, this is a book that every man, and especially every woman bedeviled by a man, will need to own.
The Male BrainFrom here she goes on to list and describe the basic neurotransmitters and hormones that shape the male brain differently than the female brain.
Scientists think of brain areas like the ACC, TPJ, and RCZ as being “hubs” of brain activation, sending electrical signals to other areas of the brain, causing behaviors to occur or not occur.
1. MEDIAL PREOPTIC AREA (MPOA): This is the area for sexual pursuit, found in the hypothalamus, and it is 2.5 times larger in the male. Men need it to start an erection.
2. TEMPORAL PARIETAL JUNCTION (TPJ): The solution seeker, this “cognitive empathy” brain hub rallies the brain’s resources to solve distressing problems while taking into account the perspective of the other person or people involved. During interpersonal emotional exchanges, it’s more active in the male brain, comes on-line more quickly, and races toward a “fix-it-fast” solution.
3. DORSAL PREMAMMILLARY NUCLEUS (DPN): The defend-your-turf area, it lies deep inside the hypothalamus and contains the circuitry for a male’s instinctive one-upmanship, territorial defense, fear, and aggression. It’s larger in males than in females and contains special circuits to detect territorial challenges by other males, making men more sensitive to potential turf threats.
4. AMYGDALA: The alarm system for threats, fear, and danger. Drives emotional impulses. It gets fired up to fight by testosterone, vasopressin, and cortisol and is calmed by oxytocin. This area is larger in men than in women.
5. ROSTRAL CINGULATE ZONE (RCZ): The brain’s barometer for registering social approval or disapproval. This “I am accepted or not” area keeps humans from making the most fundamental social mistake: being too different from others. The RCZ is the brain center for processing social errors. It alerts us when we’re not hitting the mark in our relationship or job. During puberty, it may help males reset their facial responses to hide their emotions.
6. VENTRAL TEGMENTAL AREA (VTA): It’s the motivation center—an area deep in the center of the brain that manufactures dopamine, a neurotransmitter required for initiating movement, motivation, and reward. It is more active in the male brain.
7. PERIAQUEDUCTAL GRAY (PAG): The PAG is part of the brain’s pain circuit, helping to control involuntary pleasure and pain. During sexual intercourse, it is the center for pain suppression, intense pleasure, and moaning. It is more active during sex in the male brain.
8. MIRROR-NEURON SYSTEM (MNS): The “I feel what you feel” emotional empathy system. Gets in sync with others’ emotions by reading facial expressions and interpreting tone of voice and other nonverbal emotional cues. It is larger and more active in the female brain.
9. ANTERIOR CINGULATE CORTEX (ACC): It’s the worry-wart, fear-of-punishment area and center of sexual performance anxiety. It’s smaller in men than in women. It weighs options, detects conflicts, motivates decisions. Testosterone decreases worries about punishment. The ACC is also the area for self-consciousness.
10. PREFRONTAL CORTEX (PFC): The CEO of the brain, the PFC focuses on the matter at hand and makes good judgments. This “pay total attention to this now” area also works as an inhibiting system to put the brakes on impulses. It’s larger in women and matures faster in females than in males by one to two years.
THE CAST OF NEUROHORMONE CHARACTERSThese basic differences set the stage for the rest of the book. I think one of the real strengths in her book is that she acknowledges and does not pathologize the essential differences in male brains, especially in boys where there are some real innate differences in how boys play, relate to others, and so on.
(how hormones affect a man’s brain)
TESTOSTERONE—Zeus. King of the male hormones, he is dominant, aggressive, and all-powerful. Focused and goal-oriented, he feverishly builds all that is male, including the compulsion to outrank other males in the pecking order. He drives the masculine sweat glands to produce the come-hither smell of manhood—androstenedione. He activates the sex and aggression circuits, and he’s single-minded in his dogged pursuit of his desired mate. Prized for his confidence and bravery, he can be a convincing seducer, but when he’s irritable, he can be the grouchiest of bears.
VASOPRESSIN—The White Knight. Vasopressin is the hormone of gallantry and monogamy, aggressively protecting and defending turf, mate, and children. Along with testosterone, he runs the male brain circuits and enhances masculinity.
MÜLLERIAN INHIBITING SUBSTANCE (MIS)—Hercules. He’s strong, tough, and fearless. Also known as the Defeminizer, he ruthlessly strips away all that is feminine from the male. MIS builds brain circuits for exploratory behavior, suppresses brain circuits for female-type behaviors, destroys the female reproductive organs, and helps build the male reproductive organs and brain circuits.
OXYTOCIN—The Lion Tamer. With just a few cuddles and strokes, this “down, boy” hormone settles and calms even the fiercest of beasts. He increases empathic ability and builds trust circuits, romantic-love circuits, and attachment circuits in the brain. He reduces stress hormones, lowers men’s blood pressure, and plays a major role in fathers’ bonding with their infants. He promotes feelings of safety and security and is to blame for a man’s “postcoital narcolepsy.”
PROLACTIN—Mr. Mom. He causes sympathetic pregnancy (couvade syndrome) in fathers-to-be and increases dads’ ability to hear their babies cry. He stimulates connections in the male brain for paternal behavior and decreases sex drive.
CORTISOL—The Gladiator. When threatened, he is angry, fired up, and willing to fight for life and limb.
ANDROSTENEDIONE—Romeo. The charming seducer of women. When released by the skin as a pheromone he does more for a man’s sex appeal than any aftershave or cologne.
DOPAMINE—The Energizer. The intoxicating life of the party, he’s all about feeling good, having fun, and going for the gusto. Excited and highly motivated, he’s pumped up to win and driven to hit the jackpot again and again. But watch out—he is addictively rewarding, particularly in the rough-and-tumble play of boyhood and the sexual play of manhood, where dopamine increases ecstasy during orgasm.
ESTROGEN—The Queen. Although she doesn’t have the same power over a man as Zeus, she may be the true force behind the throne, running most of the male brain circuits. She has the ability to increase his desire to cuddle and relate by stimulating his oxytocin.
From childhood on, males learn that acting cool and hiding their fears are the unwritten laws of masculinity. And especially since his testosterone surge at age thirteen, Neil had been practicing his guy face to be sure he kept his emotions to himself. For a man to physically strike a pose of self-confidence and strength, he must train his facial muscles to mask his fear.Anyway, I highly recommend the book.
Because facial muscles are controlled by the brain’s emotional circuits, scientists have been able to learn about emotions by measuring these muscles. Researchers in one study placed electrodes on men’s and women’s smiling muscle—the zygomaticus—and on the anger/scowling muscle—the corrugator. They recorded the muscles’ electrical activity as the men and women viewed emotionally provocative photos. Much to the scientists’ surprise, the men, after seeing an emotional face for just one fifth of a second—so briefly that it was still unconscious—were more emotionally reactive than the women. But it’s what happened to the men’s facial muscles next that helped me explain Neil’s guy face to Danielle.
As the experiment proceeded, at 2.5 seconds, well into the range of conscious processing, the men’s facial muscles became less emotionally responsive than the women’s. The researchers concluded that the men consciously—or at least semiconsciously—suppressed showing their emotions on their faces. Meanwhile, the women’s facial muscles became more emotionally responsive after 2.5 seconds. According to the researchers, this suggests that men have trained themselves, perhaps since childhood, to automatically turn off or disguise facial emotions. The females’ expressions not only continued to mirror the emotion they were seeing on the face in the photo, but they automatically exaggerated it, from a grin to a big smile or from a subtle frown to a pout. They, too, had been practicing this since childhood. (p. 134-135)